Microcephaly
Gene: COPB2
PMID: 37734708 - This paper reports an unrelated individual with the same homozygous variant (NM_004766.3:c.760C>T, p.Arg254Cys) identified in 2xsiblings in PMID: 29036432 (the same two siblings are also described in PMID: 34450031).
The proband is an 8.5yo Iranian female born to consanguineous parents. This individual has symptoms consistent with autosomal recessive microcephaly 19 (MIM#617800) including, global developmental delay, intellectual disability, microcephaly, seizures, spasticity, strabismus, and failure to thrive symptoms; she is unable to stand, walk, or speak.Created: 27 Dec 2023, 6:08 a.m. | Last Modified: 27 Dec 2023, 6:09 a.m.
Panel Version: 1.246
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
Microcephaly 19, primary, autosomal recessive, MIM# 617800
Publications
Loss-of-function variants in COPB2, a component of the COPI coatomer complex, in six individuals from five unrelated families. 4 are heterozygous and one family with two sibs with homozygous variant, previously reported.
All presenting with a clinical spectrum of osteoporosis or osteopaenia, many with recurrent fractures, and developmental delay of variable severity. Functional data.
Note one of the individuals with heterozygous variant had significant microcephaly in addition to the two sibs with bi-allelic variants.Created: 13 Sep 2021, 7:55 a.m. | Last Modified: 13 Sep 2021, 7:55 a.m.
Panel Version: 1.45
Two sibs with homozygous missense variant in this gene, mice homozygous for this variant had normal brain size however. Mice compound het for null allele and missense variant had some brain features, suggesting the missense variant is hypomorphic.
Sources: Expert listCreated: 2 Apr 2021, 6:31 a.m.
Mode of inheritance
BOTH monoallelic and biallelic, autosomal or pseudoautosomal
Phenotypes
Microcephaly 19, primary, autosomal recessive, MIM# 617800
Publications
Publications for gene: COPB2 were set to 29036432
Gene: copb2 has been classified as Amber List (Moderate Evidence).
Gene: copb2 has been classified as Red List (Low Evidence).
gene: COPB2 was added gene: COPB2 was added to Microcephaly. Sources: Expert list Mode of inheritance for gene: COPB2 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: COPB2 were set to 29036432 Phenotypes for gene: COPB2 were set to Microcephaly 19, primary, autosomal recessive, MIM# 617800 Review for gene: COPB2 was set to GREEN